The stoma (notice the thick cell walls) of this lilac leaf is open and shows connections with a large air cavity (intercellular space). Chloroplasts (stained purple in this preparation) are numerous in the cells of the sponge parenchyma, but are absent in normal epidermal cells. The blue-colored multicellular trichome is an extension from the epidermis. Trichomes on the surfaces of lilac leaves are not hair-shaped.